JP2006305659A - Polishing cloth dresser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the brazing material melting temperature, to suppress the falling of abrasive grains by making the brazing state of the abrasive grains uniform and stable, and further to suppress the thermal deformation of the metal support material Disclosed is a dresser for an abrasive cloth with improved flatness.
A polishing cloth dresser in which a plurality of abrasive grains are brazed to a surface of a metal support material with a brazing material, and the brazing material is interposed between the surface of the metal support material and the brazing material. A diffusion barrier layer for preventing the diffusion of the constituent elements.
[Selection figure] None

Description

  The present invention relates to a dresser for a polishing cloth used when clogging or removing foreign matter in a polishing cloth in a chemical and mechanical planar polishing (hereinafter abbreviated as CMP) process.

  Equipment for polishing the surface of a semiconductor wafer, wiring in the middle of manufacturing an integrated circuit, equipment for flattening the surface in the insulating layer formation stage, equipment for flattening the surface of an aluminum plate or glass plate used for a hard disk substrate, etc. CMP polishing is used. This CMP polishing is, for example, a method of flattening a surface to be polished by pressing the surface to be polished while supplying a slurry liquid containing fine abrasive grains to a rotating substrate to which a polishing pad made of urethane is attached. . As a matter of course, the polishing ability of this polishing pad decreases with time of use, but in order to suppress this decrease, the polishing pad surface layer is ground at regular intervals and dressed so that a new surface always appears. ing. This dressing component is called a dresser, and is made by bonding abrasive grains to a metal substrate by electrodeposition or brazing.

  Brazing usually raises the temperature to a temperature at which the brazing material melts, and it is also possible to chemically combine a part of the elements constituting the abrasive grains and a part of the elements constituting the brazing material. It becomes possible to bond the abrasive grains firmly. Patent Document 1 discloses a tool in which an abrasive layer is bonded to a support using a Pd—Cr—B—Ni-based brazing material. Patent Document 2 discloses a brazing method using a brazing material containing an element that easily forms carbides such as Fe and Mo. Patent Document 3 discloses a dresser brazed using a brazing material containing at least one of Ti, Zr, and Cr.

JP-A-62-34705 Japanese Patent Laid-Open No. 3-131475 JP-A-10-175156

  As described above, when brazing abrasive grains to a metal support, brazing materials having various compositions are used depending on the purpose, but when brazing the brazing material by heating to the melting temperature In some cases, even when heated to the melting temperature of the original brazing material, it does not melt, or the abrasive grains are not brazed.

  Therefore, conventionally, it has been attempted to improve the bondability of the abrasive grains by further increasing the brazing temperature. However, when the brazing temperature is increased, there arises a problem that deformation of the metal support material due to heat increases. End up.

  The present invention stabilizes the melting temperature of the brazing material, suppresses the falling off of the abrasive grains by uniformizing and stabilizing the brazing state of the abrasive grains, and further suppresses thermal deformation of the metal support material. An object of the present invention is to provide a dresser for an abrasive cloth with improved flatness.

The gist of the present invention is as follows.
(1) A dresser for a polishing cloth in which a plurality of abrasive grains are brazed with a brazing material on the surface of a metal support material,
A polishing cloth dresser comprising a diffusion barrier layer for preventing diffusion of constituent elements of the brazing material between the surface of the metal support material and the brazing material.
(2) The polishing cloth dresser according to (1), wherein the brazing material contains boron B.
(3) The dresser for polishing cloth according to (1), wherein the barrier layer is a carbon C concentrated layer.
(4) The dresser for polishing cloth according to (1), wherein the barrier layer is a silicon Si concentrated layer.
(5) The dresser for polishing cloth according to (1), wherein the barrier layer is a copper Cu concentrated layer.
(6) The dresser for polishing cloth according to (1), wherein the barrier layer is a nickel-Ni concentrated layer.
(7) The barrier layer is a concentrated layer containing at least one of titanium Ti, zirconium Zr, chromium Cr, hafnium Hf, vanadium V, niobium Nb, tantalum Ta, molybdenum Mo, and tungsten W. The dresser for abrasive cloths as described in (1).

  According to the present invention, when a large number of abrasive grains are brazed to a metal support, the bondability of the abrasive grains is stabilized, so that the production yield is improved. Furthermore, since there is almost no variation in the melting temperature of the brazing material, it is possible to lower the brazing temperature that has been set high with a margin in the past. As a result, there is an effect that deformation of the metal support material due to heat is reduced. Moreover, since the bondability of the abrasive grains is stabilized, there is an effect of preventing the abrasive grains from dropping during use.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
The present inventor, when brazing abrasive grains to a metal support material through a conventionally known brazing material, changing the thickness of the foil brazing, changing the coating thickness of the powder brazing, When the material is changed, when the brazing time is changed, etc., even if the temperature is raised to the melting temperature of the brazing material measured by the brazing material alone, the brazing material does not melt, or the viscosity even when melted. I noticed that it sometimes happens that the price is high. In such a case, as a matter of course, the bondability of the abrasive grains is deteriorated. If the brazing temperature is raised in order to ensure good bondability, the deformation of the metal support material due to heat becomes large, and the flatness of the dresser becomes worse.

  In view of this, the causes of fluctuations in the melting temperature of the brazing material were intensively studied. As a result, Ni-Cr-Fe-Si-B, Ni-Si-B, and Ni-Cr-Si-B brazing materials represented by JIS standard materials such as Bni-2 and Bni-5 are used. In this case, it has been found that the adhesiveness of the abrasive grains is likely to vary.

  Furthermore, as a result of a detailed analysis of the cross section of the brazing material brazed to the metal support material, boron B, which is the main constituent element of the brazing material, diffuses from the brazing material to the metal support material side. It was found that the amount of B remaining in the material was greatly reduced than the amount of B that was originally in the brazing material.

  If the diffusion of B to the metal support material can be suppressed, it is expected that the variation in the melting temperature of the brazing material will be reduced, and the variation in the bondability of the abrasive grains as described above will be reduced. The barrier layer was formed and the brazing test was repeated. Specifically, after applying various elements to the surface of the metal support material, the abrasive grains were brazed using a brazing material containing B, and the brazed state was examined. The inspection was carried out by visual inspection, and the pad was actually ground, and the condition of the abrasive grains after grinding was observed. Furthermore, the presence or absence of a decrease in B in the brazing material was measured. Through these series of tests, a barrier layer capable of stably carrying out brazing of abrasive grains was found and the present invention was completed.

  One of the specific features of the present invention is a dresser in which the barrier layer is a carbon C concentrated layer, and abrasive grains are brazed on the C concentrated layer. As the metal support material, stainless steel materials such as SUS304 and SUS430 are usually suitable. A C-enriched layer can be formed on the surface of the stainless steel by solid carburizing or gas carburizing. In the case of forming a C-enriched layer by carburizing, the C concentration is preferably 0.1% by mass or more and 1.5% by mass or less. If it is less than 0.1% by mass, the diffusion of B in the brazing material cannot be effectively suppressed. This is because even if a thickened layer of more than 1.5% by mass is formed, a further B diffusion suppressing effect cannot be obtained, and the carburizing process itself becomes difficult. The thickness of the C enriched layer may be at least 10 μm or more. This is because if it is less than 10 μm, the effect of suppressing the diffusion of B is not sufficient. The upper limit of the width is not particularly specified, but in a normal carburizing process, about 1000 μm can be carburized. However, increasing the thickness further is not preferable because it only increases the carburizing cost.

  The C enriched layer can also be formed by DLC (Diamond Like Carbon film). In this case, since the C concentration increases to nearly 100%, the thickness of the concentrated layer may be 0.2 μm or more. This is because if the thickness is less than 0.2 μm, the effect of suppressing the diffusion of B is not sufficient. With a normal ion plating method, a thickness of about 5 μm can be formed, but a sufficient effect can be obtained with a thickness of 2 μm. Even thicker than 5 μm is not preferable because it only increases the cost of film formation.

  One of the other features is a dresser in which the barrier layer is a silicon Si concentrated layer, and abrasive grains are brazed on the Si concentrated layer. A Si layer can be formed on the surface of a stainless steel material as a metal support material by, for example, CVD, ion plating, or the like. The Si concentration is determined by the amount of Si contained in the target material used when forming the Si concentrated layer, but if Si is contained at least 10% by mass, it is effective in suppressing B diffusion. If pure Si is used, it is possible to form a Si concentrated layer having a purity of 100% on the surface of the metal support material. The thickness of the Si concentrated layer may be at least 0.2 μm or more. This is because if the thickness is less than 0.2 μm, the effect of suppressing the diffusion of B is not sufficient. In a normal CVD or ion plating method, a thickness of about 20 μm can be formed, but a sufficient effect can be obtained with a thickness of 5 μm. Even thicker than 20 μm is not preferable because it increases the sputtering cost.

  Another feature is a dresser in which the barrier layer is a copper Cu concentrated layer, and abrasive grains are brazed onto the Cu concentrated layer. A Cu layer can be formed on the surface of a stainless steel material as a metal support material, for example, by electroplating, electroless plating, or the like. The concentration of Cu is determined by the plating desire composition used when forming the Cu enriched layer, but if it is contained at least 80% by mass or more, it is effective in suppressing B diffusion. Since Cu is difficult to alloy with other elements, it is preferable to form Cu having a concentration of almost 100% as a Cu concentrated layer on the surface of the metal support material. The thickness of the Cu enriched layer may be at least 0.2 μm or more. This is because if the thickness is less than 0.2 μm, the effect of suppressing the diffusion of B is not sufficient. With a normal plating method, a thickness of about 10 μm can be formed, but a sufficient effect can be obtained with a thickness of 5 μm. Even thicker than 10 μm is not preferable because it only increases the plating cost. In addition to the plating method, a Cu concentrated layer can be formed by a sputtering method.

  One of the other features is a dresser in which the barrier layer is a nickel Ni concentrated layer, and abrasive grains are brazed on the Ni concentrated layer. A Ni layer can be formed on the surface of a stainless steel material as a metal support material by, for example, electrolytic plating, electroless plating, or the like. The concentration of Ni is determined by the plating desire composition used when forming the Ni-enriched layer, but if Ni is contained at least 80% by mass or more, it is effective in suppressing B diffusion. It is possible to form a Ni enriched layer with a purity of 100% on the surface of the metal support material. The thickness of the Ni concentrated layer may be at least 0.2 μm or more. This is because if the thickness is less than 0.2 μm, the effect of suppressing the diffusion of B is not sufficient. With a normal plating method, a thickness of about 10 μm can be formed, but a sufficient effect can be obtained with a thickness of 5 μm. Even thicker than 10 μm is not preferable because it only increases the plating cost. In addition to the plating method, the Ni concentrated layer can be formed by a sputtering method.

  Another feature is that the barrier layer is a concentrated layer containing at least one of titanium Ti, zirconium Zr, chromium Cr, hafnium Hf, vanadium V, niobium Nb, tantalum Ta, molybdenum Mo, and tungsten W. A dresser in which abrasive grains are brazed onto the concentrated layer. A concentrated layer containing at least one of Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, and W is formed on the surface of a stainless steel material as a metal support material by, for example, sputtering. Is possible. The concentration of each element can be adjusted by the composition of the target material used during sputtering. If at least one of Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, and W is contained, it is effective in suppressing B diffusion. If pure elements are used, it is possible to form a concentrated layer having a purity of 100% on the surface of the metal support material. The concentrated layer of the present invention can also be formed by combining two or more elements. The thickness of the concentrated layer may be at least 0.2 μm or more. This is because if the thickness is less than 0.2 μm, the effect of suppressing the diffusion of B is not sufficient. With a normal sputtering method, a thickness of about 20 μm can be formed, but a sufficient effect can be obtained with a thickness of 5 μm. Even thicker than 5 μm is not preferable because it increases the sputtering cost.

  As the structure of the above-described barrier layer, a C concentrated layer, a Si concentrated layer, a Cu concentrated layer, a Ni concentrated layer, and at least one of Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, and W The effect of the present invention can be obtained even when a plurality of concentrated layers containing seeds are stacked. In this case, the concentration and thickness of each layer may be within the range of the concentration and thickness of each layer described above.

  In the present invention, normal diamond, cubic boron nitride, boron carbide, silicon carbide, aluminum oxide, or the like can be used as the abrasive grains. These abrasive grains can be coated with at least one selected from titanium, zirconium and chromium, or with at least one selected from titanium carbide, zirconium carbide and chromium carbide. It is. The size of the abrasive grains is preferably 10 μm to 300 μm. In order to increase the dressing force, the lower limit value may be about 50 μm or more.

  The present invention is effective particularly when B is included in the brazing material composition. Therefore, the brazing material includes Ni-Cr-Fe-Si-B, Ni-Si-B, Ni-Cr-Si. -B based Ni-based brazing material is preferred. Fe-Cr-Si-B and Fe-Si-B Fe-based brazing materials can also be used depending on the application.

  The dresser according to the present invention is manufactured as follows. First, a brazing material containing B is temporarily attached to a metal support material provided with the above-described barrier layer. When the brazing material is a foil, it can be temporarily attached by spot welding. In the case of powder, what knead | mixed the cellulose-type binder etc. with the wax powder should just apply | coat to a metal support material. The abrasive grains may be arranged on the brazing material in a predetermined pattern, for example, a regular pattern arranged in the vicinity of each vertex of a square or a triangle, or at random. The abrasive grains are arranged in a single layer at a density of about 1 to 300 per square mm. In this case, it is temporarily fixed with glue or the like so that the abrasive grains do not shift.

Next, after evacuating to about 10 ⁻³ Pa, the temperature is raised to a temperature at which the brazing material melts. Most of the binder, glue and the like are vaporized during the temperature rise. The temperature at which the brazing material is melted is preferably above the liquidus temperature of the brazing material and within about the liquidus temperature + 20 ° C. On the lower temperature side than the liquidus temperature, the unevenness of the brazing material surface becomes large, which is not preferable. Increasing the temperature above the liquidus temperature by more than 20 ° C is not preferable because it only increases the deformation of the metal support due to heat. The holding time at the brazing temperature is sufficient if it is about 10 to 30 minutes.

  By using a metal support material having a barrier layer applied to the surface of the present invention, stable brazing can be achieved at a low temperature of the liquidus temperature of the brazing material + 20 ° C.

  Using the dresser according to the present invention, the foamed polyurethane pad was continuously dressed for 30 hours while flowing water, and then the presence or absence of the abrasive grains of the dresser was examined. However, none of the abrasive grains were missing.

Hereinafter, based on an Example, this invention is demonstrated in detail.
Example 1
The surface of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm was carburized. For carburizing, a solid carburizing agent obtained by mixing 40% of barium carbonate with charcoal was used. A stainless steel disk was buried in this solid carburizing agent, and carburizing treatment was performed at the temperature and holding time shown in Table 1. The cross section of the carburized disc was analyzed with EPMA, and the C concentration and thickness of the carburized layer were measured. A Bni-2 foil with a thickness of 25 μm was spot welded on one side of a stainless steel disc carburized under the same conditions. On top of this, a diamond pattern with a particle size of 70 μm was placed in a square pattern at a density of 2 pieces / mm ² and brazed at 1040 ° C. in a vacuum for 15 minutes. The comparative material was a case where the carburizing treatment was not performed. In the evaluation after brazing, the brazing state of the diamond was observed with a microscope, and a state in which at least 40% of the diamond volume was buried in the brazing material was defined as “good” and a state of less than 40% was defined as “bad”. In addition, the diamond dropout state after polishing the foamed urethane pad for 30 hours was examined. Polishing was performed while flowing pure water with a total load of 5 kg. The results are shown in Table 1. However, the C concentration in Table 1 is the average concentration of the C concentrated layer.

  From the above, the dresser in which the C-concentrated layer is provided on the surface of the metal support material of the present invention has a good brazed state and no diamond dropout. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to the stainless steel substrate was also suppressed. In contrast, in the comparative material, about 80% of B in the brazing material was diffused to the stainless steel substrate side.

(Example 2)
A DLC film was formed on one surface of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm by ion plating. At the time of film formation, benzene gas was introduced to form a DC arc discharge plasma. The film thickness was controlled by changing the film formation time. The thickness of the DLC film as the C-concentrated layer was determined by analyzing the cross section with EPMA. The concentration analysis result of the DLC film was 98%. The comparative material was a case where the DLC film forming treatment was not performed. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 2.

  From the above, the dresser in which the C-concentrated layer is provided as a barrier layer on the surface of the metal support material of the present invention is in a good brazed state, and the diamond does not fall off at all. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The No. 11 comparative example showed the same B diffusion behavior as the No. 1 comparative example.

(Example 3)
A barrier layer containing Si was formed by sputtering on one surface of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm. The composition of the target material is Ni-10% Si, Ni-30% Si, Ni-70% Si, and pure Si. The film thickness was controlled by changing the sputtering time. The thickness of the Si concentrated layer was determined by analyzing the cross section with EPMA. The Si concentration of the Si concentrated layer was the same as the Si concentration of the target material. The comparative material was not subjected to sputtering treatment. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 3.

  From the above, the dresser in which the Si-concentrated layer is provided as a barrier layer on the surface of the metal support material of the present invention is in a good brazing state and the diamond does not fall off at all. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The comparative example No. 20 showed the same B diffusion behavior as the comparative example No. 1.

Example 4
Masking was performed on one side of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm, and a Cu film was formed on the other side by electroplating. First, after copper cyanide strike plating was performed on the SUS surface, Cu plating was performed using an aqueous copper sulfate solution. The copper sulfate plating bath is usually used in which CuSO ₄ .5H ₂ O is 200 g / L, H ₂ SO ₄ is 50 g / L, chlorine ion is 40 mg / L, and a brightener. The Cu plating thickness was controlled by changing the plating time. The thickness of the Cu enriched layer (plating thickness) was determined by analyzing the cross section with EPMA. The comparative material was not subjected to plating treatment. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 4.

  From the above, the dresser in which the Cu enriched layer is provided as a barrier layer on the surface of the metal support material of the present invention is in a good brazed state and the diamond does not fall off at all. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The comparative example No. 44 showed the same B diffusion behavior as the comparative example No. 1.

(Example 5)
A SUS304 stainless steel disc with a diameter of 70 mm and a thickness of 4 mm was masked on one side, and a Ni film was formed on the other side by electroplating using an aqueous nickel sulfate solution. The plating bath NiSO ₄ · 6H ₂ O is 150 g / L, NH ₄ Cl is 15 g / L, and boric acid is 15 g / L. The Ni plating thickness was controlled by changing the plating time. The thickness of the Ni concentrated layer was obtained by analyzing the cross section with EPMA. The comparative material was not subjected to plating treatment. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 5.

  From the above, the dresser in which the Ni-concentrated layer is provided as a barrier layer on the surface of the metal support material of the present invention is in a good brazed state and the diamond does not fall off at all. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The comparative example No. 52 showed the same B diffusion behavior as the comparative example No. 1.

(Example 6)
A film containing Ni was formed by sputtering on one surface of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm. The composition of the target material is Fe-70% Ni, Fe-82% Ni, Fe-95% Ni. The film thickness was controlled by changing the sputtering time. The thickness of the Ni concentrated layer was obtained by analyzing the cross section with EPMA. The Ni concentration of the Ni concentrated layer was the same as the Ni concentration of the target material. The comparative material was not subjected to sputtering treatment. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 6.

  From the above, the dresser in which the Ni-concentrated layer is provided as a barrier layer on the surface of the metal support material of the present invention is in a good brazed state, and diamond dropout does not occur at all except for Examples No. 61 and 62. There wasn't. In Examples Nos. 61 and 62, the diamond dropped out, but very little. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The comparative example No. 60 showed the same B diffusion behavior as the comparative example No. 1.

(Example 7)
A film containing at least one of Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, and W was formed on one surface of a SUS304 stainless steel disc having a diameter of 70 mm and a thickness of 4 mm by sputtering. Since the composition of the target material and the formed film composition were almost the same, the target material composition was the same as the film composition shown in Table 7. The film thickness was controlled by changing the sputtering time. The thickness of the concentrated layer was determined by analyzing the cross section with EPMA. The comparative material was not subjected to sputtering treatment. In the same manner as in Example 1, diamond was brazed to a stainless steel disc manufactured under the same conditions. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 7.

  From the above, the dresser provided with a concentrated layer containing at least one of Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, W as a barrier layer on the surface of the metal support material of the present invention, The brazed state is good and diamonds do not fall off at all. As a result of EPMA analysis, it was confirmed that the diffusion of B from the brazing material to stainless steel was also suppressed. The comparative example No. 73 showed the same B diffusion behavior as the comparative example No. 1.

(Example 8)
Example No. 16, No. 40, No. 46, No. 54, No. 75, and C. Concentrated layer, Si concentrated layer, Ni concentrated layer, and Ti produced under the same conditions as No. 85 , Zr, Cr, Hf, V, Nb, Ta, Mo, W were subjected to brazing treatment by placing diamond under the same conditions as in Example 1 on a stainless disc provided with a concentrated layer containing at least one of them. It was. The brazing temperature was set to 1030 ° C., slightly higher than the liquidus temperature of the brazing material, 1024 ° C., and the holding time was set to 10 minutes. In comparative material No. 20, since brazing at 1040 ° C. was not brazing, the brazing temperature was increased to 1060 ° C. and 1080 ° C. The same evaluation as in Example 1 was performed. Furthermore, the degree of warpage of the stainless steel disk was evaluated as the difference in height between the center of the disk and the position 10 mm inside from the periphery. The results are shown in Table 8.

  From the above, on the surface of the metal support material of the present invention, at least one of C-enriched layer, Si-enriched layer, Ni-enriched layer, and Ti, Zr, Cr, Hf, V, Nb, Ta, Mo, W Since the dresser to which the concentrated layer containing is added can lower the brazing temperature, there is an effect of reducing the warpage of the dresser. When the warpage is less than 50 μm, even if the pad grinding time is longer than that when it exceeds 50 μm, the effect of suppressing the reduction of the pad thickness is increased, and the uniformity of the pad thickness is improved.

Claims (7)

A polishing cloth dresser in which a plurality of abrasive grains are brazed with a brazing material on the surface of a metal support,
A polishing cloth dresser comprising a diffusion barrier layer for preventing diffusion of constituent elements of the brazing material between the surface of the metal support material and the brazing material.   The abrasive cloth dresser according to claim 1, wherein the brazing material contains boron B.   The dresser for an abrasive cloth according to claim 1, wherein the barrier layer is a carbon C concentrated layer.   The polishing cloth dresser according to claim 1, wherein the barrier layer is a silicon Si concentrated layer.   The dresser for polishing cloth according to claim 1, wherein the barrier layer is a copper Cu concentrated layer.   The dresser for polishing cloth according to claim 1, wherein the barrier layer is a nickel-Ni concentrated layer.   The barrier layer is a concentrated layer containing at least one of titanium Ti, zirconium Zr, chromium Cr, hafnium Hf, vanadium V, niobium Nb, tantalum Ta, molybdenum Mo, and tungsten W. Dresser for abrasive cloth as described in 4.